[Node Corpus] Purge orphans documents/contexts - while a corpus is deleted - Important for GDPR (fr: RGPD)

Summary

On deleting a Corpus node, the documents (contexts) are not automatically deleted.

This raises a problem with GDPR and possibility for users to delete their own data.

IMPORTANT:

• we have to conserve the contexts if they are linked to another Corpus in the tree
• so only orphan contexts must be deleted

Steps to reproduce

What is the current bug behavior?

Actually the database conserve all contexts (event orphan ones).

What is the expected correct behavior?

Previously described.

Relevant logs and/or screenshots

Possible fixes

The discussion is open to determine how the ‘purge’ can be organised:

• at the same time as the deletion of the node (Documents or/and Corpus?) to which they are linked
• independently, for example via a ‘purge’ command executed arbitrarily and regularly?